Bug 487604

Summary: built-in option for color correction doesn't work with custom EDID override
Product: [Plasma] kwin Reporter: tempel.julian
Component: colour-managementAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED WORKSFORME    
Severity: normal CC: kde, nate, xaver.hugl
Priority: NOR    
Version First Reported In: git-stable-Plasma/6.1   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: example custom EDID 2560x1440 60Hz

Description tempel.julian 2024-05-27 00:11:05 UTC 
Created attachment 169864 [details]
example custom EDID 2560x1440 60Hz

SUMMARY
According to AW EDID Editor (Windows), the attached EDID contains chromaticity information, but no color correction happens when selecting built-in color correction on KWin display settings KCM. It works with the display's default EDID when no EDID override is in effect. 

STEPS TO REPRODUCE
1. Configure to use a custom EDID as e.g. described in Arch wiki via drm.edid_firmware=edid/your_edid.bin: 
https://wiki.archlinux.org/title/kernel_mode_setting#Forcing_modes_and_EDID
(See the note about necessity to include it in initramfs, can be tricky on other distributions.)

2. Go to KWin's display settings and choose built-in color correction values.

OBSERVED RESULT
Nothing happens vs. no calibration, unlike with default EDID.

EXPECTED RESULT
It should pick up the chromaticity values provided by the custom EDID. It seems to work on Windows 11 with ACM feature or Radeon driver clamp also with custom EDID.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 6.9.2
KDE Plasma Version: 6.1 beta 1 Arch
KDE Frameworks Version: 6.2
Qt Version: 6.7.1

ADDITIONAL INFORMATION
Radeon RX 7800 XT
Comment 1 Zamundaaa 2024-07-10 15:48:16 UTC 
If you check the /sys/class/drm/card1/card1-DP-2/edid (card and connector numbers may need adjusting) file, does that match the EDID override? Also, if you check drm_info, does the drm driver expose the EDID to userspace at all?
Comment 2 tempel.julian 2024-07-11 18:24:25 UTC 
Yes, the correct custom EDID is exposed under /sys/class/drm/card1/card1-DP-2/edid . Though good news: I am not able to reproduce anymore, so apparently something's fixed it (in KWin 6.1.2?).